(1) Field of the Invention
The present invention relates to characterization of particles, and more specifically to a system and method for determining information about particle geometry based on the Doppler distribution of scattered or radiated waves resulting from relative motion between the particles and a receiver.
(2) Description of the Prior Art
A wide variety of industrial processes require non-contact measurement of materials, including separation processes, agglomeration reactors, milling operations and polymerization. For such applications, there is a need for the characterization of physical properties such as particle sizes.
Various apparatus and methods for composition and particle size measurement utilizing ultrasound are known in the art. In addition, various methods describe the use of attenuation at two discrete frequencies to monitor mean particle size in a slurry. Generally, the particle size distributions are determined by assuming a starting particle distribution; predicting attenuation at each discrete frequency; comparing the predicted attenuations with actual attenuation measurements; adjusting the distribution and then repeating this procedure until a suitable match is achieved between prediction and measurement.
Such methods have a disadvantage in that a large number of physical properties of the particles and suspending medium must be known to make the predictions. In addition, the numerical computations required to calculate the theoretical attenuations are time-consuming, and often unstable.
Those skilled in the art readily understand the wide range of potential applications for particle sizing measurements in various industries such as food, mining, pharmaceuticals, chemicals and petroleum. As such, what are needed are methods and systems for particle characterization that minimize or overcome the problems discussed above.